Cisco9300 switch with 16.09.08, ethernet connected users stop working?

[victoriabardy]

We are seeing something very strange on one of the floors in our office.  Sections of end users are finding that even though their laptop docking station has an ethernet wired connection the laptop stops working over ethernet.  I have not been able to find any issues on the switches which are running Fuji version 16.09.08.

I am thinking of just trying to reboot the switches for the floor to see if that resolves this issue.  Its a strange one and I don't see anything in the switches that suggests that is where the problem is but wanted to reach out here on the forums to make sure there were no other similar issues with sites using this version of firmware.  If you know of any cases where such behavior was diagnosed as being due to the firmware, please let me know.

Thank you in advance for your feedback.

Vicky

[Leo Laohoo]

I have seen this on our switches running IOS-XE, i. e. 3850 and 9300, and we call it "ghosting" or "ghost ports" and the workaround is a cold-reboot.  

We have seen several "variations" of this, they are: 

1. PoE stops getting delivered to a port or a series of "adjacent" ports on a switch member.  Move the same patch cable to another switch member and the PoE goes "up".  Move it back to the original port and the behaviour is the same.  Cold-reboot the offending switch member and the PoE recovers. 
2. Same goes with non-PoE devices with #1. 
3. Port is flapping (continuous down and up).  Upon inspection of the switch, NOTHING is connected to said port.  

[victoriabardy]

Hi Leo,

Thank you so much for your feedback here.  Does this correlate to any software version?  Just trying to figure out how we can stop this from continuing to happen going forward.  I rebooted the two switches involved last night.  Will find out tomorrow if the reboot resolves this issue.

Please let me know if this issue is tied to any software release.

Thank you again.

[balaji.bandi]

try latest 17.3.5 or 17.6.4 for stability.

[victoriabardy]

Hello Balaji,

Thank you for your reply.  Do you know of any identified bug that is responsible for this issue?  I was not able to find a bug that would explain this behavior.

Please let me know if you have any documented info about this as I have not been able to find any.

Thank you again.

Rgds,

Vicky

[MHM Cisco World]

can check the VLAN of these host ?

[balaji.bandi]

not really you see the bug related to cat 9300, but version of the code have bugs :

example : https://bst.cisco.com/bugsearch/bug/CSCvj76259

https://bst.cisco.com/bugsearch/bug/CSCvd46008

[victoriabardy]

Thank you so much, this is very helpful.  Do you by chance know if we can do a straight shot to 17.3.5 or 17.6.4 releases from the current Fuji 16.9.8 release the switch is currently running?  Please let me know if you do.  Thank you again for your input here.

[balaji.bandi]

yes you can upgrade direct to next version.

there will be a ROMMON Upgrade part of the upgrade process, check what method you are looking to do in the bundle or install mode.

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/17-3/release_notes/ol-17-3-9300.html

[Leo Laohoo]

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@victoriabardy wrote:
Does this correlate to any software version? 

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Ghosting happens on IOS-XE code from 16.X.X and 17.X.X.  I do not see ghosting happening on 3.X.X. 

Here is one test:  Move the offending connection to another switch member. 

NOTE:  Ghosting also causes TDR function to become unreliable and inaccurate.